It has long been customary to merchandise many products in tubes. Typical products packaged in tubes include toothpaste, lotion, caulking compound, etc.
As a result a significant industry exists in filling tubes. Currently, tube filling is generally performed by automated machinery.
Rotary piston tube filling machines are probably the most common machinery now in use for filling tubes. Typical examples of rotary piston tube filling machines are shown in U.S. Pat. No. 2,958,346 and U.S. Pat. No. 3,825,043, which are incorporated herein by reference thereto. Additionally, such machines are currently manufactured by Norden Packaging Machinery AB, Kalix Inc., Iwk Packaging Machinery, Inc. Pack. Dev. Co. Ltd. and Aktron, Inc.
Typically, rotary tube filling machines are mechanically driven by cams and chains. The tubes travel on conveyors or rotating discs to various work stations required to perform the functions necessary to fill a tube. The various functions include loading the empty tubes on the conveyor or disc in proper orientation, cleaning the interior of the empty tubes, filling the tubes, sealing the filled tubes and discharging the filled tubes from the conveyor or disc. However, with the conventional tube filling machinery, each time a new tube is used or a different fill substance is utilized, the cams and chains must be adjusted to accommodate the varying heights and angles of the tubes, the orientation marks, the time and temperature associated with sealing different tubes and the time needed to fill the tubes. Adjustment of the cams and chains is time consuming and tends to create contamination problems because of the need to oil and grease various components. Thus, after the necessary adjustments are made, time must be spent cleaning the machine to insure that the oil and grease do not come into contact with the tubes or the tubes must be cleaned before the packaging occurs. Another problem with cams is the wear associated with normal use that can cause shifting of the tubes during travel on the conveyor or disc.
Further, current tube filling machinery lacks the capacity to afford determination of adjustment corrections at the individual stations. Typically, the entire machine must be activated to be able to check any single function.